PM8000 Frequency resolution

[ausfrosty]

Hi All,

I am trying to determine if the PM8000 meets the requirements of the AEMO Mareket Ancillary Service Specificaiton Verion 7.1 in terms of Frequency resolution for Fast FCAS? Table 4 in 5.3.2  

https://aemo.com.au/-/media/files/stakeholder_consultation/consultations/nem-consultations/2021/mass...

As per the attached screen shot the frequency resolution required is <= 0.0025Hz (2.5mHz) for Fast FCAS.

If it does not is there a Schneider meter that does?

[DanL · Accepted solution]

Yes, the frequency registers have better than 2.5mHz precision on the PM8000 (when read or recorded in Float32 format).

The PM8000 uses a 40MHz clock to measure the periods of the zero crossings of the fundamental voltage.

Model	ION Module	ION Register	Measurement window	Update period	Standard Compliance	Claimed Accuracy	Precision
PM8000	Power Quality Aggregator	Power Frequency	10 s	10 s	IEC61000-4-30 Class S*	+/-10mHz	< 0.01mHz (7 digits)
PM8000	Power Meter Module	Freq	1 s	1 s	IEC61557-12 CL,02	+/-0.02% = +/-10mHz	< 0.01mHz (7 digits)
PM8000	HS Power Meter Module	HS Freq	1 cycle	1/2 cycle			< 0.1mHz (6 digits)

[ausfrosty]

Hi Dan,

Thanks for that. Just what I needed.

I was wondering where you sourced the information from? Is there any official Schneider documentation with that written down?

I will likely need to show the client that the meter satifies the requirement. If it is not in official documentation an email from local Schneider team will hopefully suffice.

Thanks again.

[Charles_Murison]

Hello @ausfrosty 

Standard Compliance and Claimed Accuracy can be found in the technical datasheet
https://www.se.com/ca/en/download/document/PLSED310058EN_Web/

Regards,

Charles